Discount calculator
Calculate how much you save and what you pay after a percentage discount. Works for any sale, coupon or promotion.
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How to calculate a discount
Calculating a discount is straightforward. First, convert the percentage to a decimal by dividing by 100. Then multiply the original price by that decimal to find your savings. Finally, subtract the savings from the original price to get the sale price.
- Savings = Original Price × (Discount % ÷ 100)
- Sale Price = Original Price − Savings
For example, a $100 item at 20% off saves you $20, and you pay $80.
Figuring out the real deal
Not all discounts are created equal. A 50% discount on an already marked-up item might not be as good as 20% off an everyday low price. Compare the final sale price, not just the percentage off, to decide if a deal is genuinely worth it.
Also consider sales tax and shipping costs — a great discount can be eroded by fees. Use our sales tax calculator to see the full picture.
Stacking discounts
Some stores allow you to combine multiple discounts, such as a store-wide sale plus a coupon. Stacked discounts are applied one after another, not added together. For example, 20% off plus an extra 10% off is a combined discount of 28%, not 30%.
To calculate stacked discounts, apply the first discount to the original price, then apply the second discount to the reduced price. The total discount percentage is (1 − (1 − D1) × (1 − D2)) × 100.
Frequently asked questions
How do I calculate a discount?
Multiply the original price by the discount percentage divided by 100, then subtract that amount from the original price. For example, $100 at 20% off: savings = $20, sale price = $80.
What's the difference between % off and $ off?
Percentage off scales with the price — a 50% discount on a $200 item saves $100. A dollar-off amount is fixed — $50 off saves $50 regardless of the price. Which is better depends on the item's price.
How do stacked discounts work?
Stacked discounts are applied sequentially, not added. Two 20% discounts applied one after the other give a total of 36% off (not 40%). Each discount applies to the already-reduced price.